import { ElementRef, OnInit, ViewChild } from '@angular/core'
import { ActivatedRoute, Router } from '@angular/router'
import { isInMobileView } from '@app/shared/misc/utils'
import { InfiniteScrollerDirective } from '@app/shared/video/infinite-scroller.directive'
import { NotificationsService } from 'angular2-notifications'
import { Observable } from 'rxjs/Observable'
import { AuthService } from '../../core/auth'
import { ComponentPagination } from '../rest/component-pagination.model'
import { SortField } from './sort-field.type'
import { Video } from './video.model'
export abstract class AbstractVideoList implements OnInit {
private static LINES_PER_PAGE = 3
@ViewChild('videoElement') videosElement: ElementRef
@ViewChild(InfiniteScrollerDirective) infiniteScroller: InfiniteScrollerDirective
pagination: ComponentPagination = {
currentPage: 1,
itemsPerPage: 10,
totalItems: null
}
sort: SortField = '-createdAt'
defaultSort: SortField = '-createdAt'
loadOnInit = true
pageHeight: number
videoWidth = 215
videoHeight = 230
videoPages: Video[][]
protected abstract notificationsService: NotificationsService
protected abstract authService: AuthService
protected abstract router: Router
protected abstract route: ActivatedRoute
protected abstract currentRoute: string
abstract titlePage: string
protected loadedPages: { [ id: number ]: Video[] } = {}
protected otherRouteParams = {}
abstract getVideosObservable (page: number): Observable<{ videos: Video[], totalVideos: number}>
get user () {
return this.authService.getUser()
}
ngOnInit () {
// Subscribe to route changes
const routeParams = this.route.snapshot.params
this.loadRouteParams(routeParams)
if (isInMobileView()) {
this.pagination.itemsPerPage = 5
this.videoWidth = -1
}
if (this.videoWidth !== -1) {
const videosWidth = this.videosElement.nativeElement.offsetWidth
this.pagination.itemsPerPage = Math.floor(videosWidth / this.videoWidth) * AbstractVideoList.LINES_PER_PAGE
}
// Video takes all the width
if (this.videoWidth === -1) {
this.pageHeight = this.pagination.itemsPerPage * this.videoHeight
} else {
this.pageHeight = this.videoHeight * AbstractVideoList.LINES_PER_PAGE
}
if (this.loadOnInit === true) this.loadMoreVideos(this.pagination.currentPage)
}
onNearOfTop () {
this.previousPage()
}
onNearOfBottom () {
if (this.hasMoreVideos()) {
this.nextPage()
}
}
onPageChanged (page: number) {
this.pagination.currentPage = page
this.setNewRouteParams()
}
reloadVideos () {
this.loadedPages = {}
this.loadMoreVideos(this.pagination.currentPage)
}
loadMoreVideos (page: number) {
if (this.loadedPages[page] !== undefined) return
const observable = this.getVideosObservable(page)
observable.subscribe(
({ videos, totalVideos }) => {
// Paging is too high, return to the first one
if (this.pagination.currentPage > 1 && totalVideos <= ((this.pagination.currentPage - 1) * this.pagination.itemsPerPage)) {
this.pagination.currentPage = 1
this.setNewRouteParams()
return this.reloadVideos()
}
this.loadedPages[page] = videos
this.buildVideoPages()
this.pagination.totalItems = totalVideos
// Initialize infinite scroller now we loaded the first page
if (Object.keys(this.loadedPages).length === 1) {
// Wait elements creation
setTimeout(() => this.infiniteScroller.initialize(), 500)
}
},
error => this.notificationsService.error('Error', error.message)
)
}
protected hasMoreVideos () {
// No results
if (this.pagination.totalItems === 0) return false
// Not loaded yet
if (!this.pagination.totalItems) return true
const maxPage = this.pagination.totalItems / this.pagination.itemsPerPage
return maxPage > this.pagination.currentPage
}
protected previousPage () {
const min = this.minPageLoaded()
if (min > 1) {
this.loadMoreVideos(min - 1)
}
}
protected nextPage () {
this.loadMoreVideos(this.maxPageLoaded() + 1)
}
protected buildRouteParams () {
// There is always a sort and a current page
const params = {
sort: this.sort,
page: this.pagination.currentPage
}
return Object.assign(params, this.otherRouteParams)
}
protected loadRouteParams (routeParams: { [ key: string ]: any }) {
this.sort = routeParams['sort'] as SortField || this.defaultSort
if (routeParams['page'] !== undefined) {
this.pagination.currentPage = parseInt(routeParams['page'], 10)
} else {
this.pagination.currentPage = 1
}
}
protected setNewRouteParams () {
const routeParams = this.buildRouteParams()
this.router.navigate([ this.currentRoute, routeParams ])
}
protected buildVideoPages () {
this.videoPages = Object.values(this.loadedPages)
}
private minPageLoaded () {
return Math.min(...Object.keys(this.loadedPages).map(e => parseInt(e, 10)))
}
private maxPageLoaded () {
return Math.max(...Object.keys(this.loadedPages).map(e => parseInt(e, 10)))
}
}